Merge tpm 2020/06/23 v1

# gpg: Signature made Tue 23 Jun 2020 12:35:03 BST
# gpg:                using RSA key B818B9CADF9089C2D5CEC66B75AD65802A0B4211
# gpg: Good signature from "Stefan Berger <stefanb@linux.vnet.ibm.com>" [unknown]
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: B818 B9CA DF90 89C2 D5CE  C66B 75AD 6580 2A0B 4211

* remotes/stefanberger/tags/pull-tpm-2020-06-23-1:
  tpm: Move backend code under the 'backends/' directory
  hw/tpm: Make 'tpm_util.h' publicly accessible as "sysemu/tpm_util.h"
  hw/tpm: Move DEFINE_PROP_TPMBE() macro to 'tmp_prop.h' local header
  hw/tpm: Move few declarations from 'tpm_util.h' to 'tpm_int.h'
  hw/tpm: Make TRACE_TPM_UTIL_SHOW_BUFFER check local to tpm_util.c
  hw/tpm: Remove unnecessary 'tpm_int.h' header inclusion
  hw/tpm: Move 'hw/acpi/tpm.h' inclusion from header to sources
  hw/tpm: Include missing 'qemu/option.h' header
  hw/tpm: Do not include 'qemu/osdep.h' in header
  hw/tpm: Rename TPMDEV as TPM_BACKEND in Kconfig
  backends: Add TPM files into their own directory
  docs/specs/tpm: Correct header path name

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>